Process of producing cellular or porous concrete



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Patented Feb. 10, 1951 1 791 820 @Qtiuvbe, 25 3 308 We;

UNITED STATES PATENT OFFICE EMRIK IVAR LINDMAN, OF STOCKHOLM, SWEDEN, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO THE AEROCRETE CORPORATION OF AMERICA, OF NEW YORK, N. Y., A CORPO- RATION OF DELAWARE PROCESS OF PRODUCING CELLULAR OR POROUS CONCRETE No Drawing. Application filed November 21, 1925, Serial No. 70,695, and in Sweden November 24, 1924.

This invention relates to an improved metha sigg and i I 1 y ffii e Ilq u@nfiy to rev t, th od of producing cellular or porous concrete formation ,of craclgs during settnigfsaiasrag suitable for various purposes. not to exceed ighty per cent of the weight In the methods of manufacture already of the total dry ingredients of the concrete known, cement or cement powder alone 01 and at least ten per cent having a grain size 55 with amxture of sand or slate maless than three-eighths of an inch. terials, su lT a's a'shesfrOm a umsliale etc. In witness whereof I have hereunto set my have been used for producing such concrete. hand. However, the said materials have certain EMRIK IVAR LINDMAN.

, m qualities that make them less suitable for 'an an economical production of porous concrete and give certain less suitable qualities to the concrete than are secured by my present invention. The present invention has for its object the production of a cheap porous con- 65 crete with an evenly distributed porosity by reason of the addition of a specific aggregate material theretog sfil'ch alditliional mafierial; comprise sla mo coa -an co e or as as o 2 coal andmincluded in 7 We? maBefore mixing the added material is to ground or crushed.

a of a and pkeanda heaats e and coke-passes? desirable properties in the 'production of porous concrete. The material is 15 added in such a state that it contains owder as well as larger garains. Ks the H ne r par- 1c es are ac yr. a 16. 1 1 team? w t as porous'bodies to preventthe forjrna on of so du iii' jjfsh nldfiglLer,,,.siry strength of the concrete will be considerably increased. Thus, with thirty-five per cent coal slag, the same strength is secured as when cement alone is used assuming the porosity to be the same in both cases. The added material should not exceed eighty per cent of the weight of the total mass, and at least ten per cent shgpldhave a grain size 4 less thaitliijei-fe' i'ghths o f an iiichrfPorous concrete withboal slag hardens more quickly than porous concrete employing cement alone.

Having now described my invention what I claim as new therein and desire to secure by 45 Letters Patent is:

The method of producing cellular concrete which consists in mixing cement, water, a. metal powder adapted to cause generation of gas, and slag so divided as to present fine hydraulizing particles and larger particles of 

